1. Field of the Invention
The present invention relates to techniques for canceling fan noise in computer systems. More specifically, the present invention relates to a method and an apparatus for canceling fan noise in a computer system by using an anti-spectra library.
2. Related Art
Rapid advances in computing technology presently make it possible to perform trillions of operations each second on data sets that are sometimes as large as a trillion bytes. These advances can be largely attributed to the exponential increase in the density and complexity of integrated circuits.
Unfortunately, in conjunction with the increase in density and complexity, the power consumption and heat dissipation of integrated circuits has also increased dramatically.
Specifically, high-end server systems can easily generate 20 kilowatts or more heat. Servers typically use powerful fans to remove heat, which can generate high levels of noise. In fact, a datacenter full of high-end servers can produce a very high decibel roar from all of the fan noise which can cause human errors while servicing high-end servers. Specifically, high noise levels can make it difficult for service engineers to communicate with each other. Service engineers may even have to use sign language to communicate with one another. High noise levels can also make it difficult for individual engineers to concentrate on the complex tasks they undertake in the datacenter. Specifically, noise levels can cause human errors that result in “No Trouble Found” (NTF) problems at customer sites, which can result in a huge cost to the server manufacture as well as causing customer dissatisfaction. Hence, techniques for reducing or eliminating fan noise are very important. These techniques are often called Automatic Noise Cancellation (ANC) techniques, or simply, noise cancellation techniques.
Present noise cancellation techniques are costly and computationally intensive. This is because present approaches sense the harmonics of a fan noise signal in real time, and then use dynamic feedback and control methods to cancel as much of the fan noise signal as possible. Since these techniques are executed in real time, they can significantly increase the computational burden on the server, which can decrease server performance.
Hence, what is needed is a method and an apparatus for canceling fan noise in a computer system without the above-described problems.